Rail bond



Nov. 9, 1954 F. c. LAVARACK RAIL BOND Filed March 13, 1951 FIG. I

|3 INVENTOR.

FREDERICK C. LAVARACK FIG.8

ATTORNEY.

United States Patent ilice 2,693,972 Patented Nov. 9,. 1954 RAIL BOND Frederick -C. Lavarack, Montclair, N. JL, assignorto Railroad Accessories Corporation, New York, N. Y., a corporationzof New York Application March. 13, 1951, Serial No; 215,213

1 Claim. (CL 2871-10.?!)

This. invention. relates to. electrical conductors particularly "electrical conductors known .as. rail bonds, andespecially. to .the form. of:rail bondsknown as head-oferail bonds.

A principal Object of-this .invention is to construct a bond'of the type specifiedv whichwill. be extremely inex pensive to construct, extremely easy to install, formed of aminimum of material, exhibiting a minimum of obstruction to-dragging railway equipment parts and which may be most securely mechanically and electrically attached ina cavity in the side of a rail head by the use. of .a hammer and punch, andis so formedthatthe possibility of contacting a driving punch with the edgeof the receiving orifice is obviated.

Other objects andadvantages will appear as the .descrip tion of the particular physical. embodiment selected to illustrate the invention progresses and the novel features. will be particularly pointed out-in the-appended claim.- Indescribing the invention in detail and the partic-.

view of oneterminalof mybond with a fragment of the connecting cable before being swaged; Fig.4 is a cross sectional view of thedevice as shown by Fig. 3, after being swaged, on theplane indicatedbytheline lVIV' viewed in the direction of. the arrows at the ends. of the line; Fig. 5 is a cross sectional view of the device of.

Fig. l onthe same plane as =thatof Fig. 2, but showing the terminal firmly aflixed in the rail orifice; Fig. .6-is a cross sectional view of the deviceasshown by'Fig. 5 on the plane indicated by the line VIVI viewed in the direction of thearrows at theends of the line;-Fig. 7 is a. fragmentary crosssectionalview of the. deviceof Fig. l on thelsame plane-as Fig. 2, viewed in thedirection ofthearrows showing the relation of the rail, splice bar andlbond; Fig.. 8 is a side. elevational .view, with .a part. broken. away, showing apunchused in connectionwithmy invention; Fig. 9 is a cross sectional view of the device.

asshown by-Fig. 8 on..the.plane'indicated/by the line IX-''IX viewed in the..directi0n. ofthearrows atthe ends oflthe line.-

Those skilled in the art of railway signalling are well aware that .a .most wvulnerableszpartroft arailway track circuit is the bond connecting the abutting ends of adjacent rails because itis exposed to all kinds of weather and isspositioned so that it is likely to be struckflandr damaged-:by draggingrailway equipment; lt is'also well known that these bonds are generallypositioned on the outside of theztrack rail, in most casesaeach 39 feet along theatrackway; so that a considerable-expense iscaused byxthe mere :purchase thereof anda.stilhgreaterexpense to :properly/install them.

My invention provides a bond of the head-of-rail type which requires, relative to present day bonds, a minimum of material, and it is, therefore, possible to sell them at a minimum price. My bond is so constructed that it may be applied to a rail head by a relatively unskilled person so as to make the most intimate mechanical and electrical contact-with themet-al of .a rail. My.

bond, is also so constructed that the terminalplugs thereof are most intimately'and satisfactorily, mechanicallyand electrically connected tothe usual cable andthe aflixing of the plugs of the bondinto the'rail headsuassists; rather than detracts, from-the intimate mechanical and electrical.

contact between the cable and' the plug;

Heretofore I have devised a bondwith a terminal'of the same general type as the terminal shown in the pres? ent case but, in this'case; I have the-added feature of: a peripheralwall at. the top or outside :head ofnthe-teie minal to contain the end ofa driving punch, togain the advantage; among others of -preventing the punchfrom.

striking and perhaps mutilating the corner of the orifice in which the terminalis affixed. I also initially form my terminal so. that. it.is a greater diameter near the. outer face thereof so-that when a cable is attached thereto, by 'swaging, and electrical connection-is'made with the cable atthis pointthan was securedin former constructions.

In order to secure the above mentioned advantages,"

and-others, I construct and apply my bonds as illustrated in the accompanying drawings :and as hereinafter described.

Fig. l illustrates the ends of two abutting rails of. a railway track. and have been designated 1 and '2. .My

bond-designated as a whole by B includes-an electrical: conducting cable 3and two plugs 4 and'5,.each'plug. seated in a cavity openingin the. side face of a raiLhead:

The conductor 3 may be of any-appropriate or usually' be solid or stranded. I prefer: a

used metal. and maystranded cable.

The plugs, as 5, of my invention are of metal; I prefer malleable copper, in fact, dead soft copper.; The plugs are of a somewhat: cylindrical form southat are of circular cross section. I prefer to have the side 6' of the plugslOpingyso thatthe plug, in general, is in the form of a frustrurnof a cone; although I do not mean to exclude the use of straight sides so that the plug-.is approximately cylindrical. The inner end face 7 of the-plugis shown as substantially a truncated cone.

This particularendface is preferred, but I do not mean to exclude a construction involving other endfaces'such as fiat. The outer end of the plug5 is formed with a flat face 8 for themajor'portion of its area, and this area'is surrounded by a, .preferably, low, narrow circumferentialwall 9. These plugs are formed by any usualor ordinary mechanical. method, asby drilling, with a cavity 10. This cavity 10 has its longitudinalaxis preferably: displaced from the central longitudinal axis of the plug 5 as well shownc'inFigs; 2, 3 and 4, but I' do'not mean. to'exclude. a contsniction inwhich the cavity is central 'ofthe plug 5.

After the cavity 10.1 is formed in plugS, one end of an electrical conductor, as the cable 3, of a plurality of strands, is inserted'in the'cavity 10 as far as it will go. and then the entire periphery.- 6 is compressed or swaged so that thematerialof plug 5 and the material of cable S-are intimately'brought together or driven together and the strands of the cable somewhat distorted so that all of the interstices are obliterated, with.the material of the plug protruding therein,- and so that the material of plug 5 and the materialof conductor 3 are, in 'effe'ct, one, both mechanicallyv and electrically, or at any-rate, they arepreferably. so intimately squeezed one into the other that there is practic'allytno opportunity for.

air or moisture to enter or get betweentheyarious parts so" as to start corrosion. and..inj'uryor deteriorate the mechanical and electrical union. Thisswagingis sodone that-the plug,.5 .becomessubstantially cylindrical and of an external diameter suchthattheplugmay be inserted in. astan dard, inch,.rail head. orifice by then-fingers;

The diameterof the; initially formed=plug,gass-shown by Fig. 3, iso-reduced tothe;greatesttextent.onconraboutathe'v line indicating theplane uponwhich. section IV" is taken.-' As a consequence a great; dealLofi. metal.Risa-compressed in and about this region so that the metal of the plug quite thoroughly enters into the interstices between the several strands of the cable 3, especially at this place, that is, just behind the face 8. As a consequence, the

a much morelfirm and intimate mechanical.

the plugs.

connection between the cable 3 and the plug 5, is certainly such that substantially all air or moisture is excluded at this point. The plug 5 after the swaging, is preferably of a length such that the outer face 8 of the plug will, when the plug is inserted by hand, just about reach the position even with the face of the rail head, as shown in Fig. 2, but after being driven, as hereinafter described, the outer corner of the wall 9 will lie just without the cavity 11 of the rail head, that is, the outer corner of the wall 9 will be out beyond the face 12 of the rail, as shown in Fig. 5.

After the plug 5 is put into place, as shown in Pig. 2, it is driven into place to assume the position as shown in Fig. 5. In order to permanently afiix the plug 5 in the cavity 11, a punch 13, driven by a hand hammer is placed against the outer face or area 8 and the punch is then hammered to drive the plug 5 firmly home and expand it within the cavity 11.

The punch 13 has the usual handle portion 14, preferably of polygonal cross section and a driving end 15. The extreme end 15 of the punch is a plane at a right angle to the longitudinal axis of the punch 13, preferably, but I do not exclude an inclined or other formed face. Adjacent the end, the punch is reduced in external diam eter and has a partial arcuate periphery 16 terminating in a plane parallel to the longitudinal axis of the punch, that is, the plane through the points 17 and 18 of Fig. 9. The punch is further formed adjacent the end with an arcuate cavity 19 parallel to the longitudinal axis of the punch and opening at the end face and in the plane parallel to the longitudinal axis. The outer periphery of the end 15 just fits within the circumferential wall 9 and the cable 3 is received within the cavity 19, and the major portion of the surface of this cavity 19 substantially fits a portion of the periphery of the cable 3 to which it is adjacent. The net result is best shown perhaps in Fig. 6 in dotted lines.

Upon driving punch 13 with a suitable tool, as a hand hammer, the plug 5 is driven into the cavity 11 until it seats on the end surface 20 of that cavity and then is driven firmly and tightly against the end surface 20 and the side walls of the cavity 11. In this operation the plug 5 is thoroughly compressed and expanded sidewise so as to make a perfect mechanical and electrical connection with the inside curved walls of the cavity 11. It contacts the face of the walls so tightly that air and moisture are substantially excluded.

The driving of the plug, as hereinbefore described, also tends to further compress the material of the plug in and around the strands of the cable 3 and to force the strands of the cable closer and more intimately to gether. This more effectively prevents any air or moisture to enter therebetween.

It should also be noted that the end of the punch 13 covers the major portion of the area 8, in fact, almost all of the area, so that the driving is most effective to expand the plug into the cavity 10 because practically all of the metal of the plug is confined between the punch and the walls of the cavity. It should also be noted that even a careless workman would not strike the edge 21 of the cavity in the rail head with the end of the punch, because the protecting circumferential wall 9 entlrely surrounds the end of the punch, so that when it is once seated, even if the blows of the driving hamrn er tend to cause the punch end to move sidewise there will be no opportunity for the end to contact the corner 21 or the inside surface of the cavity wall. Furthermore the punch 13 is, in effect, positioned between the cable 3 and the protecting wall 9 so that it is quite perfectly centralized and the driving force applied is applied at the proper place.

From the hereinbefore given description it will be seen that my improved bond terminal and bond is so constructed and so applied that an extremely good electrical and mechanical contact is obtained between the surface of the plug and the curved surface of the cavity 11. It is further to be observed that with my construction, as the final heavy blows to finally affix the plug in the cavity 11 are applied to the plug when it is substantially all wlthm the cavity 11, the plug 5 is driven to a good secure and properly positioned seat in the cavity 11.

It should further be noted that, unlike other headof-rail bonds of the prior art, my bond has substantially only a quite flexible stranded metallic cable outside of the cavities in the rail head. Such a body can give and not break when struck by dragging railway rolling stock equipment, whereas bonds of the prior art, having a solid portion of the bond protruding from the rail head cavity are more likely to be broken or cut off under such conditions.

It is true that the circumferential wall may protrude slightly from the face of the rail head, but it is quite thin and even if struck by dragging equipment, it would be merely sheared or bent and could not transmit sufiicient of the striking force to substantially loosen or draw the plug 5 out of the orifice in the rail head.

A further most important feature of my bond is that it is practically immaterial to the proper affixing of my plug in the rail bead cavity that the cavity is made deeper than standard. If the cavity is deeper than standard, the plug merely sinks deeper into the rail head, and when it has contacted the end wall of the cavity, the driving force applied to its outside face expands it just as properly as though the cavity were the standard depth. The absence of any enlargement upon my plug 5 that is intended to rest against the outside face of the rail head is also a decided advantage because there is nothing to be distorted or damaged when an attempt is made to afiix the plug in a hole which is deeper than standard.

Above all, as the substantial portion of the plug is entirely Within the cavity in the rail when being expanded, every bit of distortion or expansion aids in completely filling the cavity in the rail head and holding the plug in place therein. This is unlike that form of bond in which there is a protuberance extending outwardly beyond the side face of the rail and which may be hammered quite forcibly without any substantial expansion or distortion taking place in the material within the cavity in the rail head.

It is further to be noted that my bond is constructed of three parts only, and these thre parts are so firmly and permanently united that there is absolutely no danger of any one part becoming separated from the others.

By providing a protecting wall 9 to receive and properly seat the driving punch 13, one is able, even if inexperienced, to more quickly drive a plug to a secure seat in the cavity 11 without danger of injuring the! punch or mutilating the edge of the cavity in the rail.

Although I have particularly described one particular physical embodiment of the invention and explained the construction and principle thereof, nevertheless, I desire to have it understood that the form selected as merely illustrative, but does not exhaust the possible physical embodiments of the idea of means underlying my invention.

What I claim as new and desire to secure by Letters Patent is:

A rail bond, including, in combination, a cable of electrically conducting metal, a plug of malleable metal formed with an end driving face and with a longitudinal cavity with its axis displaced from the longitudinal axis of the plug and opening in the driving face only, an end of said cable positioned in said cavity and the interstices of the cable having the metal of the plug projecting therein and swagingly in contact therewith, a thin circumferential wall projecting beyond the driving face of the plug through which the cable protrudes for confining the end of a driving punch therebetween and the cable and rail connecting means on the other end of the cable.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,578,901 McCaulley Mar. 30, 1926 2,138,404 Haas Nov. 29, 1938 2,180,318 Deems Nov. 14, 1939 2,237,338 Dale Apr. 8, 1941 2,289,221 Sorensen July 7, 1942 2,622,903 Lavarack Dec. 23, 1952 

